Synthesis of all-silica DDR zeolite in an environment-friendly way

The synthesis of all-silica DDR zeolite is challenging and not green. The lengthy synthesis time, use of expensive template, solvents (water and ethylenediamine) and fluoride lead to high material cost, capital investment on autoclave and waste disposal issues. Here we propose an environment-friendly synthesis of all-silica DDR zeolite with significantly reduced consumption of organic template and solvent. The use of toxic solvent (ethylene diamine) and mineralizing agent (fluorides) was avoided. The obtained DDR samples were characterized by XRD, SEM, NMR, FT-IR, TGA, and nitrogen adsorption. High quality DDR crystals with high yield can be obtained in 2d with molar recipe of 1.0 SiO2: 1.0 H2O: 0.05 ADA, which is almost an atomic economic synthesis. Compared with regular hydrothermal synthesis, the Shelton E factor was significantly reduced. (C) 2016 Elsevier Inc. All rights reserved.